This section provides background information related to the present disclosure which is not necessarily prior art.
As the level of our living is growing, Wireless-Fidelity (Wi-Fi) has been widely applied to respective aspects of our life, e.g., at home, in an office, in a shopping mall, on a bus, etc., so that Wi-Fi signals are widespread in the respective aspects of our life. It is the most desirable for people arriving at some place to ask for Wi-Fi available around them. In the meanwhile, radiation of the Wi-Fi signals has also become an important aspect within which people are concerned. Although Wi-Fi brings a lot of convenience to people, the widespread Wi-Fi signals have also become a killer to our health. Particularly as routers become more and more functionally powerful, and both their transmission rates and transmit power have been significantly improved, the radiation of these signals has become more pronounced as a result.